The purpose of the invention is therefore to improve the damping behavior of a pneumatic cylinder with the generic features during the end position damping.
The solution of this problem results from the content of the Claims including advantageous embodiments and developments of the invention, which follow this description.
In its fundamental idea the invention provides that the control chamber of the control valve is connected with an area of the damping arrangement in which release pressure exists and that a closure arrangement with a controlled closure element is connected in the duct connection by means of which the respective release pressure which exists at the time by means of which the begin of the damping which is characterized by an increase in pressure in the damping chamber can be an trapped in the control chamber and such acts as a fixed control pressure onto the control piston of the control valve and defines the opening time of the control valve for the enabling of the vent path.
The invention is therefore based on the advantageous principle, in that the pressure which respectively exists in the damping chamber at the beginning of the damping is normally lower than the working pressure, is used as a threshold for the beginning of the damping with the discharge of the air which still exists in the damping chamber, in that this pressure which respectively currently exists in the damping chamber and/or in the connection duct at the beginning of the damping is used for controlling the control valve which enables the vent path for the damping chamber. The invention teaches that accordingly the pressure on the ventilation site is determined as the control pressure for the control by means of the connection created between the control chamber of the control valve and the area of the damping arrangement in which release pressure exists, and this duct connection is interrupted by the controlled movement of the closure element at the beginning of the damping and therefore fixes the control pressure for the control valve. To this extent, the mode of operation of the end position damping is independent of the operating method of the pneumatic cylinder, whether with faster or with slower piston travel, since the invention teaches that exclusively the pressure which exists on the side of the ventilation at the time when the damping begins, is important. As a result, this substantially increases the energy range and/or working range of the damping device as taught by the invention